The invention relates to a method for the prevention of fire spreading inside the feeding channel leading into the fire chamber of a furnace for solid fuel and a furnace for the realization of this method.
The spreading of fire within the feeding channel can be prevented if it is made impossible for the flames to spread within the entire channel, across the section of the feeding channel which opens into the fire chamber proper.
U.S. Pat. No. 4,181,082 suggests that a fire inside the feeding channel of a furnace be extinguished by water. For this purpose, a water line is connected to the upper area of the feeding channel, which, at its point of connection, is closed by a valve which in turn is controlled by a temperature sensor. At a given temperature, this sensor opens the valve, permitting water to flow into the feeding channel, the water passing over the temperature sensor and lowering its temperature, causing the valve to close again as soon as the temperature has been lowered sufficiently. This method has the disadvantage that not only the fire inside of the feeding channel, but also the fire within the fire chamber will be extinguished, the fuel being fed into the fire chamber at that point being totally soaked. If the water flow should be reduced for the purpose of preventing the drenching of the fuel, the fire no longer will be extinguished with certainty, because only partial areas of the fuel will be wet. It is another disadvantage of this method of record that it creates a sump inside the feeding channel which can be removed only through cleaning.
It is the goal of the invention to prevent a spreading of the fire within the feeding channel without markedly impairing combustion inside the fire chamber.